Sound post for violins



Dec. 18, 1928. 1,695,783

R. w. STEPHENSON SOUND POST FOR VIOLINS Filed April 21, 1927 RM BY mmmm Ad. ATTORNEY.

Patented Dec. 1 8, 1928.

UNITED STATES PAT N OFFICE.

emu w; smrnmvson, or murmur, IOWA.

me P08! FOR VJZOL'INS.

bpp'kicltibh fled April 21, 1927. Serial N0. 185,311.

My invention has reference to sound-posts for violins and other stringed infltrmnents, andhas for its purpose to' improve the action of such instruments, resirlting in an increase in the number of overtones, more mellow tones, and tonesof greater power and penepurpose to control v'ibratims of the. strings, and assist inholyding'the bridge of the instrument in a state oz! rest. These it does but imperfectly, andthe purpose of the pres;

ent invention is'to render the function of the sound-post more effective, to the extent of greatly changing the character of the instrument. This it does by providing the soundpost with an auxiliary vibratory device, 0 pable of transmitting a multiplicity of tones, and thereby in'croasi'ngithe' volume and sweetness of all of the tones. It does this without any noticeable encroachment upon the violin air, and in no way mutes the tones of the instrument.

The above named, and other features and advantages of the invention will be more fully understood from the following specification, taken in connection with the accompanying drawings, in which;

Fig. 1 is a cross-section through the body of a violin, near the bridge mounted thereon.

Fig. 2 is a fragmentary longitudinal sec tion of an instrument, also in the vicinity of the bridge. I

Fig. 3 is an enlarged side view of the in vent-ion, detached.

Fig. 4 is an upper end view thereof.

Fig. 5 is a lower end view thereof.

Fig. 6 is a detail of the post 5.

The reference number 1 indicates the sounding-board of a violin, and 2 the back thereof, said parts being united at their edges by side-pieces 3. Mounted on the sound-board 1 is a bridge 4, and secured between said sound-board and the back 2 in the vicinity of the bridge 4 is a sound-post 5, to which is fixeda spiral lamina 6, of gradually increasing radius upwardly. Said lamina is preferably attached to the post by means of a spiral channel 7 in the post to receive the innor edge of the lamina. Other methods of attachment may be employed, however, and the post and lamina may be formed in a single piece. Said parts arehothpreferably formed of wood of a kind best adapted to the purpose, but other materials may be substituted for one or both of said parts.

The best results are found to be secured by giving the lamina a winding of approximately two and one-halt times around the post, ending in aradial edge 8 at its widest part, the extreme end of said lamina being reduced to thethinncss of the bladeof a knife.

There is a marked similarity between the form of the lamina 6 and the lamina spiralis ossea of the cochlea of the human ear, the

membranes of which are given a winding of two undone-half turns about a stem or modiolus of bone, with which the sound-post 5 compares. Associated with the lamina spi ralis of the ear is the scala media, supposed to bethe sound classifier, which assists in separating the musical tones from the more inharmonious sounds, and noises, It deter mines the range of the tones and overtones and it is believed that the operation of the present invention is largelysimilar to that of the parts just mentioned.

The spirals of the lamina 6 lie in substantially parallel position between the upper and lower boardsof the violin, winding about the post 5 as a modiolus and affecting the vibrations thereof, producing more overtones, rendering the tones more mellow, and giving them greater power and penetrating quality.

In the embodiment set forth herein the pitch of the spirals is shown as about equal to the diameter of the post 5, but this pitch may be varied at will, so as to produce the best results, and the lamina may be placed It will be observed that the spirals of the lamina contain an infinite number of radii, of different lengths, which are believed to be capable of accomn'mdating an infinite number of tones, and this is believed to be the secretof the numerous overtones and improvement in the tone of the instrument,

which is secured thereby.

The sound-post and lamina thereon is preferably made of a size to permit of its being turned inwardly through the opening near the bridge of the instrument, and positioned therein by means of a sound-post setter, specially provided for such purpose. The invention can thereby be appliedto instruments already manufactured and in use. In some cases, however, a larger term of the device would be desirable in which case it could he builtinto the instrument at tie time of construction thereof. or the instrument can be taken apart for the purpose of installing the same therein and again put together.

It has been den'ionstrated that the inveution c uit uans to the principles inentioned and flullills its functions in a delinite and positive manner. It improves the tone ot a cheap l'actorv produced violin with a char-- a tcristic factory tone to such an extent that the lllftl'llllltilt is hardly recognizialile. Haw nionious result can 1; attained liv faulty and -areless liovving ol the strings which an not ordinaril; be secured on the ii -est instruments.

The position ol the sound-pos in the violin or other instrument may be, varied to suit the particu ar requirements ol? he i. strunient, the same as is done with the soundposts of a simpler form novv in use, and th sound-post set forth herein, vcitli the lamina attached thereto, appears to possess temperamental qualities of its oivn, such as are corninonlv i und in the stringed instruments themselves.

Better results are secured by positioning the invention with the straight edge 8 directed toward the neck ot the instrument. and in line with the strings thereof.

The same OllQCtS that have been set forth herein as being produced by the spiral lainina can be secured to some extent by using independent laininze or disks of varying diameters spaced apart on the post 5.

What I claim and desire to secure by Letters Patent. is:

l A device of the class described. coma sound-post adapted for support in '.e lied" of a stringed musical instrument. a l: niina wound in a contiiuuuis spiral iost adapted for support in the ngred musical instrument, :1! d a or gg rai'luallv increasing radii wound on said eoundpost.

23. A device of the class descrihed. compri ing a central post support adapted for being positioned hetn'een the soundingdioard and bacl; of a stringed musical instrument and a spiral laiiziina o-t gradually increasin; radii Wound thereon, and provided at its widest wart with a night edge projected radiallv :troin said support.

In testimony whereof I afiix my signature.

RALPH. \V. STEPHENSON. 

